Additional experiments would be required to determine if the F-3: POSTN+ sublining transcriptional cell state could transform into the RA-expanded14 F-5: CD74hiHLAhi sublining or F-6: CXCL12+ SFRP1+ sublining fibroblast populations under JAK/STAT stimulation. This evidence concerns the gene SFRP1 and rheumatoid arthritis.